IGF-1 LR3: Patient Information & Safety Notes

Name: IGF-1 LR3: Patient Information & Safety Notes
Creator: OmniRx Health

Also known as IGF1-LR3, Long R3 IGF-1, Long-R3-IGF-I

Other names: long-r3-igf-1, long-r3-igf-i

IGF-1 LR3 is a recombinant analogue of insulin-like growth factor-1 with an extended half-life due to an arginine substitution and N-terminal extension. It has been used in research settings. It is NOT approved by the FDA for bodybuilding or general health use.

NOT FDA-approved for any human use. Mecasermin (Increlex), an FDA-approved recombinant IGF-1 product for selected pediatric growth failure, is a different drug. IGF-1 LR3 is a research compound whose safety in humans is not established.

Reviewed by the OmniRx Health clinical team•Last reviewed Jul 4, 2026

In plain language

What Insulin-Like Growth Factor-1 LR3 is used for

Used in research settings to study IGF-1 signaling; it is not an established muscle-building treatment

Taking this medicine

How it is administered

Subcutaneous injection
Sublingual troche

Read before you decide

Risks and precautions

Risks and warnings

Injection site irritation, rash
Nausea
Hypoglycemia (low blood sugar) — significant risk given IGF-1's insulin-like activity
Potential pro-oncogenic effects (IGF-1 promotes cell proliferation)

Who should not take it

Active or past malignancy (IGF-1 drives cell growth)
Diabetes or insulin-dependent conditions (hypoglycemia risk)
Pregnancy or breastfeeding

Common questions

Patient questions

Is IGF-1 LR3 FDA-approved?

No. IGF-1 LR3 is not FDA-approved for any use. An approved pharmaceutical IGF-1 (mecasermin/Increlex) exists for pediatric growth failure only — IGF-1 LR3 is a different compound used in research contexts, not approved for human performance or health use.

Related medications

CJC-1295 / IpamorelinGHRH analogue + GHSR agonist combination — research compoundResearch / not FDA-approved Sermorelin / IpamorelinGHRH analogue + GHSR agonist combination — compoundedCompounded / off-label HexarelinGrowth hormone secretagogue (GHSR agonist) — research compoundResearch / not FDA-approved

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This information is educational — not medical advice.

This page is provided for general educational purposes and summarizes publicly available data from sources such as the U.S. Food & Drug Administration. It is not a substitute for the judgment of a licensed clinician and should not be used to start, stop, or change any medication. It may be incomplete or out of date, and individual circumstances vary. Always talk with your prescriber or pharmacist about your specific medications and health conditions. If you think you may have a medical emergency, call 911.

Sources & References

Learn more about where our data comes from and how we write and review medical content.